More than a decade ago, I attended a workshop by Mike Sigman in Minneapolis. I had been reading his material and watching his videos for a couple of years, soaking up his teachings on the ground path. After studying martial arts for over 25 years at that point, and the internal arts for over a decade, it was new material when I was introduced to Chen taiji through Jim and Angela Criscimagna. Because of Mike Sigman, and his use of internal terms I had never heard before, I sought out Jim and Angela and began studying with them.
One of the exercises we did at Sigman's workshop in Minneapolis was a drill using the ground to rebound force through the body to use in striking.
This is called different things in different arts. It is the backbone of "borrowing" energy -- when someone attacks you and you use their incoming force and "bounce" it back to them. I demonstrated this and discussed it in an article last October in Kung Fu Magazine.
It appears to be the same principle Bruce Lee used in his one inch punch.
In a nutshell, you press the rear foot into the floor and let the ground strength rebound through the body and out the hand (or shoulder or whatever you're using). This requires a LOT of practice. It also requires relaxation, dantien rotation, and a whole-body connection that carries the ground to the hand (or attacking part). In the past, we have used this to break boards. It's deceptive because you don't wind up, you don't cock the shoulder and you don't drive the arm forward.
You simply use proper body mechanics to bounce the ground through the hand.
I was reminded of this a couple of weeks ago by my friend, Evan Yeung. He is quite a student of the martial arts -- he studies bagua and chen tai chi, also karate and contact flow through the Guided Chaos folks headed by John Perkins. I realized that even though this bouncing or rebounding or borrowing energy is part of our arts (Taiji, Hsing-I and Bagua), I hadn't isolated the practice of it in a couple of years.
Stay tuned -- in a couple of days we'll tape a video demonstrating this.